Wiktionary
chamber ensemble
n. A musical ensemble of modest size, to play chamber music; can be more specifically named after its number (from duo to nonet) and/or type(s) (e.g. wood, brass, strings) of instruments.
Usage examples of "chamber ensemble".
I'm toying with the idea of setting up a chamber ensemble, if you're interested.
I also keep Robert up to date on the activities of Ernie and Howie, both of whom have been released and are leading highly productive lives, Ernie as a city-employed counselor for the homeless and Howie as a violinist with a New York-based chamber ensemble.
He moved his hands restlessly in the air, as if conducting a chamber ensemble hidden behind the sand hills, and I noticed his badly scarred palms.